Why Sydney Sweeney Calls Her On-Set Prep ‘Psychotic’—and Feels Bad for Julianne Moore

Here’s how it goes: Sweeney enters a scene chatting up crew members, perhaps cracking jokes, and then, boom, they call “Action!” Next thing you know, she’s screaming, crying and diving deep into her character’s trauma without a moment’s hesitation. And when the director shouts “Cut!” she snaps right back to questioning where the tears came from and whether anyone needs water. Jimmy Fallon’s audience practically fell out of their chairs at the description—and I’m honestly surprised you’re not fainting over the details.

Now, before you assume this is all method actor bravado, understand that Sweeney’s approach pays dividends in her latest film, Echo Valley. The Hulu competitor—no, wait—Apple TV+ thriller (premieres June 13) reunites her with Oscar winner Julianne Moore, plus Domhnall Gleeson, Kyle McLachlan, Fiona Shaw, Edmund Donovan and newcomer Albert Jones. Directed by BAFTA honcho Michael Pearce and scripted by Emmy nominee Brad Ingelsby, the film centers on Moore’s Kate, a mother striving to reconnect with her estranged daughter, Claire (Sweeney). The tension spikes when Claire shows up at Kate’s doorstep “hysterical and covered in someone else’s blood,” per an official synopsis, igniting a fierce fight-or-flight scenario that tests the limits of maternal sacrifice. Sources: People Magazine, Dotdash Meredith.

When Fallon asked what it was like sparring with Moore, the Immaculate actress practically winced on national television: “I felt so bad, ’cause I’m vicious. I’m really vicious.” Apparently, Moore was just as kind off-camera as she was fierce on it, earning high praise for her warmth and generosity during those heated mother-daughter confrontations. If you’re keeping score, that’s a major co-star endorsement and a pretty clear indicator that Sweeney’s psychotic method isn’t messing with the veteran actor’s feelings.

So, here’s your handy recap: Sweeney’s abrupt emotional flip, her apologies to Moore, the Apple TV+ premiere date (June 13), plus a cast and crew stacked with award power. Clearly, you needed this cheat sheet. Glad I could untangle that for you.